Sanding machine



Oct. 26, 1948. 5, NEWTON 2,452,205

SANDING MACHINE Filed Nov. 29, 1945 flzi/m jflwm/y 7/ INVENTOR.

Patented Oct. 26, 1948 STATES PATENT OFFICE SANDING MACHINE Herman S. Newton, Temple, Tex. Application November 29, 1945, Serial No. 631,551

3 Claims. 1

This invention relates to sanding machines and more particularly to adjustable belt sanders especially adapted for working on wood.

The objects of the invention are: First, to provide a self contained power unit having parallel sanding belt spindles arranged for relative adjustability by virtue of an extensible spindle arm; second, to provide an adjustable and removable work table for supporting work in relation to the sanding belts on said spindles in various angular positions; third, to provide individual tensioning means for the belts on said spindles to compensate for variations in length; and fourth, visible means for predetermining angularity of the belts through a range of at least 90.

With the foregoing objects as paramount, the invention has further reference to certain features of accomplishment which will become apparent as the description proceeds taken in connection with the accompanying drawings wherein:

Figure 1 is a perspective view of a sanding machine constructed according to the invention.

Figure 2 is a rear elevational view of the individual belt tensioning means per se.

Figure 3 is a fragmentary perspective view of one of the belt tensioning devices.

Figure 4 is a fragmentary view showing the angle controllin and indicating means for the belt spindle column of the machine, and

Figure 5 is a side elevational view of Figure 4.

Continuing with a more detailed description of the drawing, reference is primarily made to Figure 1 wherein numeral Ill denotes the base of the sanding machine, supporting a curved standard II, on the upper end of which is formed a boss i2 longitudinally bored to receive a sturdy stub shaft i3. The stub shaft i3 is formed on and extends outwardly from the outer tubular element M of two telescopically related elements, the companion element l5 being slidable in the element M to form an adjustable spindle column for one or a pair of sanding belts iii. A cap Ila is secured to the end of shaft l3 by means of a locking screw |5a entering a threaded opening Ilia in the shaft.

The outer member Id of the spindle column which carries the stub shaft l 3 carries on its lower end a mounting arm I! for a motor l8 and intermediate its ends there is mounted a collar IQ for adjustment longitudinally on the member I 4. A set screw 20 is provided to secure the collar in adjusted positions on the member l4. 3 Further reference to this collar and its purpose will be made presently.

The spindle column assembly, composed of members I and i5 forms the subject matter in part of applicants Letters Patent No. 2,416,493, and except for minor variations, to adapt the same to the structure hereindescribed, there is 2 little difference in the design, construction and purpose as described in said application.

The extensible element It of the spindle column carries a housin 2i on its upper end in which is mounted a bearing 22. The bearing 22 is supported in the housing 2i by diametrically opposed set screws 23 entering the housing from the sides so that the hearing will be capable of limited oscillative displacement. A spindle shaft 24 is mounted rotatably in the bearing 22 and, by virtue of the pivotal displacement of the latter, the spindle 24 is capable of similar axial displacement.

Since the spindle 24 carries rollers 25 over which the sanding belts i6 operate, tension on the belts to insure trackin is increased or diminished by actuating an adjusting screw 26 which is mounted in an extension 27 and is adapted to bear upon the bearing 22 and hold the same in adjusted positions in relation to the housin 2!.

The armature shaft of the motor l8 carries one or two rollers 28 over which the belts l6 travel and it is preferred that these rollers, as well as rollers 25 be rubber surfaced to insure adequate traction for the belts l6.

Mounted upon the spindle column member M and extending under the upper lead of the sanding belts i6 is a platen 29 which aifords a backing for the belts against resistance of the work applied thereto.

In order tosupport the work in relation to the belt or belts H5 at various angles up to a work table 30 is mounted forwardly of the belts it by means of anarm 3|, integral with the table and slotted at 32. A bolt 33 extends through the slot 32 into a tapped and threaded aperture in the boss i2 of the supporting standard Ii. Obviously by loosening the bolt 33 and movin the table 30 outwardly from the belts I8, the spindle column may be moved from the position shown in Figure 1 to a vertical position, after which the bolt 33 is again tightened when it is required to operate the belts H5 in a horizontal position, the table 30 is removed entirely. A stop 33a in the form of a set screw limits movement of the column by engagement with the stop by the motor [8 when vertical adjustment is effected. This stop also precludes damage to the pointer 31 by preventing its engagement with the shoulder defined by the cut away portion of a collar 34 (Figure 4).

In Figures 4 and 5 is shown the means by which the degree of movement of the spindle column is predetermined. This means consists simply of.

the said collar 34, formed on the boss it which has a segment 35 cut therefrom. A stop pin 36 is embedded in the stub shaft l3 and extends radially outward and upon rotation of the shaft i3,

the pin moves against the wall of the recess 35 to stop rotation of the shaft and consequently the 'sible to fix theang'le of the spindle column at any intermediate position.

Embedded also in the shaft 13 i a pointer 31 which moves over a scale 36 to indicate by the graduation thereon the degrees of displacement of the spindle column from the vertical. By virtue of this arrangement, the operator is enabled to predetermine the angle of the sanding belt or belts IS in relation to the table 30 on which the work is horizontally disposed.

It has been stated that one belt may be used on the spindles or two belts carrying different grades of abrasive. The rubber surfaced rollers 25 and 28 over which the sanding belts travel may be either single or double, as desired. However, in using two belts, it often happens that they difler somewhat in length, hence will be of unequal tension under individual tension,

A tensioning means is provided which consists of an arm 39, retained by a set screw 49 (Figure 2) in a hole made in the collar I9, carried adlustaby by the spindle column. The arm extends between the leads of belts 16 across their major axes. The arm carries spaced apart collars H which are bored transverse to the axis of the arm 39 to receive shanks 42 carrying on their upper ends arcuately shaped shoes 43 which are held on the shanks by nuts 44, threaded upon the ends of the shanks tobear against the shoes 43.

The arcuated face of each shoe 43 bears against the inner surface of the rear lead of its respective belt 16, as shown in Figure 1 and to provide for individual tension of the shoes on the belts, a double torsion spring 46 surrounds the arm 39 intermediate the collars 4i, having its ends bent to embrace each of the shanks 42. It being anchored to the arm 39 intermediate its ends by means of a pin 46 embedded in the arm, it is obvious that the spring is effective to yieldingly hold the shoes 43 against the belts I6.

Provision is made through the medium of nuts 41, threaded onto the lower ends of shanks 42 for holding the shanks and consequently the shoes against axial or rotative displacement. However, when it is found necessary to adjust the position of a shoe in relation to a belt, its nut 4'! is loosened to permit such adjustment and again tightened. Adjustments of this nature are sometimes required to insure tracking and to prevent overlapping of the belts on the rollers although this may be accomplished to a certain exent by the spindle adjusting screw 26, previously described.

The arm 39 has a slot 39a in its outer end to receive a tool by which it is rotated to increase or decrease the tension of spring 45.

Manifestly, the construction as shown and described is capable of some modification and such modification as may be construed to fall within the scope and meaning of the appended claims is also considered to be within the spirit and intent of the invention.

What is claimed is:

1. A sanding machine including a base and stand, a spindle column consisting of telescopically related tubular members, the outer of said members being mounted intermediate its ends on said stand for oscillative movement through an arc of 90"; a motor and spindle mounted on one end of said column, a parallel companion spindle carried by the end of the inner tubular member of said column and capable of rotative and limited pivoted displacement thereon, sanding belts surrounding said spindles, driven by said motor, an arm having one end mounted rotatably on the outer of said telescopically related members and extending laterally therefrom between the leads of said sanding belts and having relatively spaced collars thereon, a pair of parallel shanks intermediate the leads of said belts, and adjustably retained by said collars, an arcuate shoe carried by each of said shanks, a torsion spring surrounding said arm and having its ends bearing on said shanks, for imposing individual tension on said belts by means of said shoes and means for rotating said am to vary the tension imposed by said spring;

2. In a sanding machine, a base and stand, a

spindle column consisting of tubular, telescopically related members, the outer of which is supported by said stand intermediate its ends for limited oscillative displacement, a spindle carried at each end of said column, one of which is pivotally displaceable in relation to the companion spindle, means for driving one of said spindles, belts surrounding said spindles, a lateral arm attached at one end to the outer member of said column, a pair of spaced collars thereon, parallel shanks supported by said collars intermediate the leads of said belts, an arcuate shoe carried by each of said shanks, a torsion spring surrounding said lateral arm for imposing tension on said shanks for individually tensioning said belts and means for varying the tension of said spring.

3. In a sanding machine, a base and stand, a spindle column composed of telescopically related sections, one of which sections is oscillatably mounted on a shaft extending from said stand, a motor and spindle supported by the lower end of said column driven by said motor, a companion spindle carried by the opposite end of said column, and mounted for pivoted displacement intermediate its ends, rubber surfaced belt rollers on said spindles, sanding belts mounted on said rollers, an arm mounted rotatably by one'end on the oscillatable section of said column, spaced collars mounted on said arm, a pair of shanks intermediate the inner and outer leads of said belts, whose lower ends are retained in said collars, arcuate shoes mounted on the upper ends of said shanks, a torsion spring surrounding said arm and bearing on said shanks for imposing individual tension on said belts and means for rotating said arm in its mounting to vary the tension of said spring.

HERMAN S. NEWTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS FOREIGN PATENTS Country Date- France Sept. 11, 1924 Number Number 

